[ty] Move class_member to member module (#20837)

## Summary

Move the `class_member` function to the `member` module. This allows us
to move the `member` module into the `types` module and to reduce the
visibility of its contents to `pub(super)`. The drawback is that we need
to make `place::place_by_id` public.

## Test Plan

Pure refactoring.

crates/ty_python_semantic/src/lib.rs

@@ -34,7 +34,6 @@ mod db;
 mod dunder_all;
 pub mod lint;
 pub(crate) mod list;
-mod member;
 mod module_name;
 mod module_resolver;
 mod node_key;

crates/ty_python_semantic/src/member.rs

@@ -1,73 +0,0 @@
-use crate::{
-    place::{Place, PlaceAndQualifiers},
-    types::Type,
-};
-
-/// The return type of certain member-lookup operations. Contains information
-/// about the type, type qualifiers, boundness/declaredness, and additional
-/// metadata (e.g. whether or not the member was declared)
-#[derive(Debug, Clone, PartialEq, Eq, salsa::Update, get_size2::GetSize)]
-pub(crate) struct Member<'db> {
-    /// Type, qualifiers, and boundness information of this member
-    pub(crate) inner: PlaceAndQualifiers<'db>,
-
-    /// Whether or not this member was explicitly declared (e.g. `attr: int = 1`
-    /// on the class body or `self.attr: int = 1` in a class method), or if the
-    /// type was inferred (e.g. `attr = 1` on the class body or `self.attr = 1`
-    /// in a class method).
-    pub(crate) is_declared: bool,
-}
-
-impl Default for Member<'_> {
-    fn default() -> Self {
-        Member::inferred(PlaceAndQualifiers::default())
-    }
-}
-
-impl<'db> Member<'db> {
-    /// Create a new [`Member`] whose type was inferred (rather than explicitly declared).
-    pub(crate) fn inferred(inner: PlaceAndQualifiers<'db>) -> Self {
-        Self {
-            inner,
-            is_declared: false,
-        }
-    }
-
-    /// Create a new [`Member`] whose type was explicitly declared (rather than inferred).
-    pub(crate) fn declared(inner: PlaceAndQualifiers<'db>) -> Self {
-        Self {
-            inner,
-            is_declared: true,
-        }
-    }
-
-    /// Create a new [`Member`] whose type was explicitly and definitively declared, i.e.
-    /// there is no control flow path in which it might be possibly undeclared.
-    pub(crate) fn definitely_declared(ty: Type<'db>) -> Self {
-        Self::declared(Place::bound(ty).into())
-    }
-
-    /// Represents the absence of a member.
-    pub(crate) fn unbound() -> Self {
-        Self::inferred(PlaceAndQualifiers::default())
-    }
-
-    /// Returns `true` if the inner place is unbound (i.e. there is no such member).
-    pub(crate) fn is_unbound(&self) -> bool {
-        self.inner.place.is_unbound()
-    }
-
-    /// Returns the inner type, unless it is definitely unbound.
-    pub(crate) fn ignore_possibly_unbound(&self) -> Option<Type<'db>> {
-        self.inner.place.ignore_possibly_unbound()
-    }
-
-    /// Map a type transformation function over the type of this member.
-    #[must_use]
-    pub(crate) fn map_type(self, f: impl FnOnce(Type<'db>) -> Type<'db>) -> Self {
-        Self {
-            inner: self.inner.map_type(f),
-            is_declared: self.is_declared,
-        }
-    }
-}

crates/ty_python_semantic/src/place.rs

@@ -1,7 +1,6 @@
 use ruff_db::files::File;
 
 use crate::dunder_all::dunder_all_names;
-use crate::member::Member;
 use crate::module_resolver::{KnownModule, file_to_module};
 use crate::semantic_index::definition::{Definition, DefinitionState};
 use crate::semantic_index::place::{PlaceExprRef, ScopedPlaceId};
@@ -233,50 +232,6 @@ pub(crate) fn place<'db>(
     )
 }
 
-/// Infer the public type of a class member/symbol (its type as seen from outside its scope) in the given
-/// `scope`.
-pub(crate) fn class_member<'db>(db: &'db dyn Db, scope: ScopeId<'db>, name: &str) -> Member<'db> {
-    place_table(db, scope)
-        .symbol_id(name)
-        .map(|symbol_id| {
-            let place_and_quals = place_by_id(
-                db,
-                scope,
-                symbol_id.into(),
-                RequiresExplicitReExport::No,
-                ConsideredDefinitions::EndOfScope,
-            );
-
-            if !place_and_quals.place.is_unbound() && !place_and_quals.is_init_var() {
-                // Trust the declared type if we see a class-level declaration
-                return Member::declared(place_and_quals);
-            }
-
-            if let PlaceAndQualifiers {
-                place: Place::Type(ty, _),
-                qualifiers,
-            } = place_and_quals
-            {
-                // Otherwise, we need to check if the symbol has bindings
-                let use_def = use_def_map(db, scope);
-                let bindings = use_def.end_of_scope_symbol_bindings(symbol_id);
-                let inferred = place_from_bindings_impl(db, bindings, RequiresExplicitReExport::No);
-
-                // TODO: we should not need to calculate inferred type second time. This is a temporary
-                // solution until the notion of Boundness and Declaredness is split. See #16036, #16264
-                Member::inferred(match inferred {
-                    Place::Unbound => Place::Unbound.with_qualifiers(qualifiers),
-                    Place::Type(_, boundness) => {
-                        Place::Type(ty, boundness).with_qualifiers(qualifiers)
-                    }
-                })
-            } else {
-                Member::unbound()
-            }
-        })
-        .unwrap_or_default()
-}
-
 /// Infers the public type of an explicit module-global symbol as seen from within the same file.
 ///
 /// Note that all global scopes also include various "implicit globals" such as `__name__`,
@@ -701,7 +656,7 @@ fn place_cycle_initial<'db>(
 }
 
 #[salsa::tracked(cycle_fn=place_cycle_recover, cycle_initial=place_cycle_initial, heap_size=ruff_memory_usage::heap_size)]
-fn place_by_id<'db>(
+pub(crate) fn place_by_id<'db>(
     db: &'db dyn Db,
     scope: ScopeId<'db>,
     place_id: ScopedPlaceId,

crates/ty_python_semantic/src/types.rs

@@ -89,6 +89,7 @@ mod generics;
 pub mod ide_support;
 mod infer;
 mod instance;
+mod member;
 mod mro;
 mod narrow;
 mod protocol_class;

crates/ty_python_semantic/src/types/class.rs

@@ -7,7 +7,6 @@ use super::{
     function::FunctionType, infer_expression_type, infer_unpack_types,
 };
 use crate::FxOrderMap;
-use crate::member::Member;
 use crate::module_resolver::KnownModule;
 use crate::semantic_index::definition::{Definition, DefinitionState};
 use crate::semantic_index::scope::{NodeWithScopeKind, Scope};
@@ -22,6 +21,7 @@ use crate::types::enums::enum_metadata;
 use crate::types::function::{DataclassTransformerParams, KnownFunction};
 use crate::types::generics::{GenericContext, Specialization, walk_specialization};
 use crate::types::infer::nearest_enclosing_class;
+use crate::types::member::{Member, class_member};
 use crate::types::signatures::{CallableSignature, Parameter, Parameters, Signature};
 use crate::types::tuple::{TupleSpec, TupleType};
 use crate::types::typed_dict::typed_dict_params_from_class_def;
@@ -37,8 +37,8 @@ use crate::{
     Db, FxIndexMap, FxOrderSet, Program,
     module_resolver::file_to_module,
     place::{
-        Boundness, LookupError, LookupResult, Place, PlaceAndQualifiers, class_member,
-        known_module_symbol, place_from_bindings, place_from_declarations,
+        Boundness, LookupError, LookupResult, Place, PlaceAndQualifiers, known_module_symbol,
+        place_from_bindings, place_from_declarations,
     },
     semantic_index::{
         attribute_assignments,
@@ -3272,7 +3272,7 @@ impl<'db> ClassLiteral<'db> {
 
     /// A helper function for `instance_member` that looks up the `name` attribute only on
     /// this class, not on its superclasses.
-    pub(crate) fn own_instance_member(self, db: &'db dyn Db, name: &str) -> Member<'db> {
+    fn own_instance_member(self, db: &'db dyn Db, name: &str) -> Member<'db> {
         // TODO: There are many things that are not yet implemented here:
         // - `typing.Final`
         // - Proper diagnostics

crates/ty_python_semantic/src/types/member.rs

@@ -0,0 +1,120 @@
+use super::Type;
+use crate::Db;
+use crate::place::{
+    ConsideredDefinitions, Place, PlaceAndQualifiers, RequiresExplicitReExport, place_by_id,
+    place_from_bindings,
+};
+use crate::semantic_index::{place_table, scope::ScopeId, use_def_map};
+
+/// The return type of certain member-lookup operations. Contains information
+/// about the type, type qualifiers, boundness/declaredness, and additional
+/// metadata (e.g. whether or not the member was declared)
+#[derive(Debug, Clone, PartialEq, Eq, salsa::Update, get_size2::GetSize)]
+pub(super) struct Member<'db> {
+    /// Type, qualifiers, and boundness information of this member
+    pub(super) inner: PlaceAndQualifiers<'db>,
+
+    /// Whether or not this member was explicitly declared (e.g. `attr: int = 1`
+    /// on the class body or `self.attr: int = 1` in a class method), or if the
+    /// type was inferred (e.g. `attr = 1` on the class body or `self.attr = 1`
+    /// in a class method).
+    pub(super) is_declared: bool,
+}
+
+impl Default for Member<'_> {
+    fn default() -> Self {
+        Member::inferred(PlaceAndQualifiers::default())
+    }
+}
+
+impl<'db> Member<'db> {
+    /// Create a new [`Member`] whose type was inferred (rather than explicitly declared).
+    pub(super) fn inferred(inner: PlaceAndQualifiers<'db>) -> Self {
+        Self {
+            inner,
+            is_declared: false,
+        }
+    }
+
+    /// Create a new [`Member`] whose type was explicitly declared (rather than inferred).
+    pub(super) fn declared(inner: PlaceAndQualifiers<'db>) -> Self {
+        Self {
+            inner,
+            is_declared: true,
+        }
+    }
+
+    /// Create a new [`Member`] whose type was explicitly and definitively declared, i.e.
+    /// there is no control flow path in which it might be possibly undeclared.
+    pub(super) fn definitely_declared(ty: Type<'db>) -> Self {
+        Self::declared(Place::bound(ty).into())
+    }
+
+    /// Represents the absence of a member.
+    pub(super) fn unbound() -> Self {
+        Self::inferred(PlaceAndQualifiers::default())
+    }
+
+    /// Returns `true` if the inner place is unbound (i.e. there is no such member).
+    pub(super) fn is_unbound(&self) -> bool {
+        self.inner.place.is_unbound()
+    }
+
+    /// Returns the inner type, unless it is definitely unbound.
+    pub(super) fn ignore_possibly_unbound(&self) -> Option<Type<'db>> {
+        self.inner.place.ignore_possibly_unbound()
+    }
+
+    /// Map a type transformation function over the type of this member.
+    #[must_use]
+    pub(super) fn map_type(self, f: impl FnOnce(Type<'db>) -> Type<'db>) -> Self {
+        Self {
+            inner: self.inner.map_type(f),
+            is_declared: self.is_declared,
+        }
+    }
+}
+
+/// Infer the public type of a class member/symbol (its type as seen from outside its scope) in the given
+/// `scope`.
+pub(super) fn class_member<'db>(db: &'db dyn Db, scope: ScopeId<'db>, name: &str) -> Member<'db> {
+    place_table(db, scope)
+        .symbol_id(name)
+        .map(|symbol_id| {
+            let place_and_quals = place_by_id(
+                db,
+                scope,
+                symbol_id.into(),
+                RequiresExplicitReExport::No,
+                ConsideredDefinitions::EndOfScope,
+            );
+
+            if !place_and_quals.place.is_unbound() && !place_and_quals.is_init_var() {
+                // Trust the declared type if we see a class-level declaration
+                return Member::declared(place_and_quals);
+            }
+
+            if let PlaceAndQualifiers {
+                place: Place::Type(ty, _),
+                qualifiers,
+            } = place_and_quals
+            {
+                // Otherwise, we need to check if the symbol has bindings
+                let use_def = use_def_map(db, scope);
+                let bindings = use_def.end_of_scope_symbol_bindings(symbol_id);
+                let inferred = place_from_bindings(db, bindings);
+
+                // TODO: we should not need to calculate inferred type second time. This is a temporary
+                // solution until the notion of Boundness and Declaredness is split. See #16036, #16264
+                Member::inferred(match inferred {
+                    Place::Unbound => Place::Unbound.with_qualifiers(qualifiers),
+                    Place::Type(_, boundness) => {
+                        Place::Type(ty, boundness).with_qualifiers(qualifiers)
+                    }
+                })
+            } else {
+                Member::unbound()
+            }
+        })
+        .unwrap_or_default()
+}